Ammeter



April 23, 1929. D; v. FALLoN AMMETER Filed Oct. 13, 1927 @Harmen Patented Apr. 23, 1929.

, unire DAVID VQFALLON, or DETROIT, M1oH1eAN,-Ass1e1von ToDoNGANnLECmaIG MAn,- y

FACTURING CO., OIEiDlil'llEtfnlT, MICHIGAN, A.V CORPORATION OF MICH-IIGnfklg,4 f

A AMMETER. .I v

Appl-mation fliedl October' 13,A 1927.Y serial N'orezaeesf This invention'relates to ammeters for in- Y dicating the direction of flow of current ina circuit7 andthe Objectis-to provde an am'- meter of very simple construction' and provide in conjunction therewith a permanent mafmet and means for vari ino' the extent4 and power ofthe "magnet'iield to hold the pointerf ofr the'ammeter at Zero indication whenl there is noflow of currentlin'the circuit.v rlhe principal features of the invention are involved inthe arrangement ofthe parts to'provide a portion only of the circuit L adjacentv an armature with which the pointer l vided with coils'through which the current is provided, the armature of vwhichxliesbetween a part through whichthe current flows and the permanent magnet and further inthe construction and means employed vto vary the magnetic 'eld of the permanent magnet. These ,objects and the several'novel features of the inventionjare hereinafter more fully described and claimed, 'and' thet preferred form of construction of an ammeterembodying my invention is shown in the vaccompanying drawingin' whichy Fig. l is a view of theammeter showing the pointer and the graduated scale relative to'which the pointer -is movable. r

Fig. 2' is a view Vwithv the face plate' removed, -the pointer beingrebroken away to show the adjustablearmature 'for the 'permanent magnet'. c

Fig. 3 is-asectiontaken Online of Fig. 1. v l y v- Y Fig; 4.- is a view. of the face plate from'tlie rear taken on the sectionline 'i-L-of Fig. 3.

Fig. 5V pointer member. y

Fig. 6 is a 'detail-in section practically on line 6--6 of Figu. f y lThe construction of the ammeter heretofore has been somewhat complicated being proispassed to influence thepointer member..

. 'In my improved device the coils are dispensed wit-lf'andy 'current flow maybe through the face plate of thefarmat'ure or an additional band or strip 4of metal. adjacent Vthe same asl 'is hereinafter. described.

L In the preferred construction; the ammel ter consists of a baseV platell and a faceplate Zsupported "on the base and screws H passingl ltherethrough and is a detail in"perspective' of; the' by spacer blocks extending tov the l rear of the base asfshown i particularly inFigsj'S and 6 from which it Y' will beseen thateach screw and the spacer blocks k'are insulated from thebase plate l and are in electrical ycontact with the lface' Vplate Q.V` Binding nuts (are'provided on the screws to hold the same in place and to pro=- l l vide means :for attaching Vterminals of the circuit thereto; so that thetwo.l screws and the face plate Qform-part ofthe circuit." An ad-vv in lisA a plug` 8 having aconed socket at'the forward end forthe pointer shaft 9 andthe member 7 may also-.have a similar socket for vthe opposite end' of the. pointer shaft.

Thepointer 10 issecured to this/shaft bey l tween'thevplates l and Zandl extends out`-V ward through an aperture 11 inthjefaee plate'l A- and thence upwardy tothe graduation marks relative 'to Ywhich the end kof the pointer is movable in either direction. This pointer as will be readily understood fromFig.v 5, this entirel pointer `member may be-A formed of:V blank sheet metaland provided with the wing likeportions 13V forming an armatureL which "is provided with a dependingportion 12 pro- 'viding a counter-balance for-the pointer and,V

normally lies practically parallelv with the Y ymember 7 and between the two'screws .Lt-4;! i

1 There is alsoprovided on `theinner side of V*g5 1 the base l apermanentmagnet 14 of the usual'horseshoe type and this is supportedy with thetwop'oles of the magnetA each Side Y' off the pointer shaft 9 'as'willbeunderstood 1i. l y from Figi 2.@ VIt will be seen in the said figure',f v`90 that the 'pointer armature lf3-lies directlyv on a -linebetween'the two screwgmembersfl andv between the two poles ofthe i'na'gnetandv just forward of the twopolesof the magnet.

The ermanent n nafnetlssuv orted ini lace by a'screwy 15 extending through the'pl'ate l"V .and provided with anut l'to bindfthe same in place. An armature 17fis provided .for the permanent magnet 'which consists1of thin f i sheet metal provided with a slotted extension' 18' fitting `overthe screw l5 atfthe upper: endvandisheld-infplaceonthescrew bya nut l19`.; i.

l'By loosening the'nutythis'armature,mayfbel moved relative .tothe polel pieces to increase f '20 l the other to cause the needle to ,stand at zero or decrease the powerof the magnetic i'ield and can be turned readily to oneV side or the other of a line passing from the screw l5 to the armature shaft 9 so that one or the other ofthep'ole pieces is of strongerniagnetic influence. By moving the armature 17 for v ward or backward, calibration on the charge or discharge "side `is advanced or retardedto anrequal degree. By moving the armature diagonally to the magnet, calibration on the charge and discharge side will be advanced to an unequal degree. The armature also acts as a keeper for they magnet. A

This arrangement enables the structure to-beinade without any great accuracy as to balancing ofthe various partsolE the needle Y ior instance asany discrepancy in that re-` spect may be compensatedfor by the magnet armature. Further, the counterbalancing member 12 maybe bent slightly one way or by iniiuenceof gravity. The ammeter is designed lto be used with the pointer member extending vertically asshownin Fig. l.`

,frplicity .of the parts" and the arrangementy Itfis therefore evident that, by the sim? I thereof, they device is extremely inexpensive y a large scale.

1 coil of thecircu-it-wire about the pointerv cuit.

in vconstruction land Vvery little labor lisin v y volved in assembling the various 'partsV and any extreme accuracy in manufacture is obviated, adapting the same for production on It is further evident that the structure may be embodied in avcasing or otherwise mounted for use without departing from the spirit of this invention. A particular feature of the invention is ink dispensing,withg the usual armature and makin-g the plate, orY bar 'in conjunction with the plate, part of the oir With Vthe, armature and such coil as l ,previouslygusech considerable exactness in manufacture and considerablecare ininstalling the same Vin Vproper relation with the pointer armature was required. By the ar-v f rangement and construction herein described,

theA partsare automatically brought to the i necessary position vby nthe mereA act oit insert,-

ingthe screwsto assemble the parts, 'Ifpref lier to use a small phosphor bronze bar 7 betw'een the two screws abut this may be readily Y Vdispensed withasv the plate 2 itself may provide the path for current between the screws i i.et+-4l. The pointer armature 13A lies quite close vto the plate 2 and vbar 7 as here shown,

Y, and the magnetic fieldset up by the flow of other way.V` Thus,if the armature be .used on j v albatte'ryfline, as in the usual automobile, the

'current in one direction Vor the lother across the plate v and bar 7 tends to turn the pointer armature'at a right angleto thev direction of flow of the current moving the pointer mem "ber inone direction on its'axis on flow of currentvone'way and .in the, other directionl the dir ectionfand extent of the charge ordisi tion, what I claiinis-f i l. In an ammeter, a base plate and a face. plate in spaced relation, screwsextending charge of the battery will be indicated by the pointer.

Havingl thus briefly described my inven from the face plate and through the base plate in electric' contact with the face plate and insulated from the base plate providing terminals for an electric circuit, the face plate providing a path for electric current from-one terminalY to the'other, a pointer member provided with an armature pivotally plate providing a path for electriecurrent fromV one terminal to `the other, a `pointer .f

member `pivotally supported between the plates and having an enlarged portionfpro-` viding an armature adjacent the. face plate and normally on a line extendingbetween the plate having polar` portions adjacent the pointer armature magnetically hol-ding the armature of y'the pointer, theit'ace plate having an aperture through which the pointer extends and vbeing further provided with graduation-srelative to which the pointer is movable. `y V In an ammeter, apairof plates of nonmagnetic metal, means for securing thesame together in spaced relation, said means being in insulated relation'with the base plate and providing electrical terminals in electricaly f said screws, a permanent magnet on the base iie contact with the face plate, the face plate pro#` viding `a path for electric current from one' terminal to the other, a pointer member pivotallysupported betweenl the plates and having an armature, a permanent magnet onv the base vplate having polar portions V,adj acent the pointer armature holding thesame ini neutral position with itslongitudinal axis parallel to the line` passingbetween the two screws, said faceplate havii'rg;any apertureV through which the pointer member extends,

therebeingrgraduations thereon for the said pointer., and means for varying the magnetic field' distributienet the perinaneiitmagnet.

4. vIn an ammeter, abase plate and a face Y plate, screws extending through the plates f adapted to hold the saiiie'in spaced relation and being in electricalV contact" with Vthe kface plate and insulatedy fromfthe baiseplate,` said screws providing terminals 'atthe-,rearof the base plate for an Velectric circuit, a pointer member provided With an armature pivotally supported between the plates and having a pointer end extending through an aperture 5 provided in the face plate7 said face plate having calibrations for the pointer, a permanent magnet between thesaid plateshaving pole'pieees adjacent the pointer armature,l

and an armature adjustable thereon diagonally of the center line thereof and toward or from the pointer armature. o x Y ln testimony whereof, I Sign'th'is speeiv DAVID v. FALLONT Vfieation. l 

